import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.channels.FileChannel;

public class TransferTo {
    public static void main(String[] args) {
        if (args.length != 2) {
            System.out.println("arguments: sourcefile destfile");
            System.exit(1);
        }

        try (FileChannel in = new FileInputStream(args[0]).getChannel();
            FileChannel out = new FileOutputStream(args[1]).getChannel()) {
            in.transferTo(0, in.size(), out);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}
